Eco-friendly dyeing of cotton fabrics with microbial pigments: Anionic modification for superior color, antibacterial, hydrophobic and UV protection properties

Cotton has always been a major raw material for the textile industry, and clean and efficient processing methods have been the focus of research. Microbial pigments have demonstrated significant potential as sustainable dyes, garnering considerable attention. However, the suboptimal dyeing performance and low dye absorption rate of microbial pigments when applied to cotton fabrics have hindered their widespread adoption. In this study, we present a straightforward and efficient anionic modification method for cotton fabrics, aimed at preparing multifunctional dyed cotton textiles. First, anionically modified cotton textiles, with a high density of sulfhydryl groups on the surface, were prepared by reacting (3-mercaptopropyl)triethoxysilane with cotton textiles. Raman spectroscopy, FTIR, EDS, SEM, WCA, and TGA were employed to characterize the structure and properties of the modified cotton textiles. The dyeing performance of the modified cotton textiles was significantly enhanced, with the dyeing K/S value reaching 17.6, 8.87 times higher than that of the unmodified cotton textiles, and the dye uptake rate increased by 98 %. The dyed textiles not only exhibit excellent color fastness but also demonstrate antibacterial, UV, and hydrophobic properties, with a bacterial inhibition rate exceeding 95 %, a UV protection factor of 153.4, and a contact angle of 126.1°. This process effectively addresses the inefficiency of microbial pigments in cotton fabric dyeing, while simultaneously imparting multiple functionalities to the cotton textiles, offering a novel approach to green textile processing. • The fabrics are dyed with the environmentally friendly green microbial pigment. • Mercapto-modified anionic cotton fabrics were prepared and innovatively used for dyeing with prodigiosins pigment. • The dyeing effect and dye uptake of the modified cotton fabrics are greatly improved. • The preparation of multifunctional dyed cotton fabrics with antimicrobial, anti-ultraviolet, and hydrophobic properties.